CMF / CRF Details

CMF ID: 7828

Road diet (Convert 4-lane undivided road to 2-lanes plus turning lane)


Prior Condition: Roadways with 2 lanes in each direction

Category: Roadway

Study: Validation and Application of Highway Safety Manual (Part D) in Florida, Abdel-Aty et al., 2014

Star Quality Rating: 3 Stars   [View score details]
Rating Points Total: 90
Crash Modification Factor (CMF)
Value: 0.56
Adjusted Standard Error:
Unadjusted Standard Error: 0.15
Crash Reduction Factor (CRF)
Value: 44   (This value indicates a decrease in crashes)
Adjusted Standard Error:
Unadjusted Standard Error: 15
Crash Type: All
Crash Severity: All
Roadway Types: Principal Arterial Other
Number of Lanes: 4
Road Division Type: Undivided
Speed Limit:
Area Type: Urban
Traffic Volume: Minimum of 2000 to Maximum of 28500 Annual Average Daily Traffic (AADT)
Average Traffic Volume:
Time of Day: All
If countermeasure is intersection-based
Intersection Type:
Intersection Geometry:
Traffic Control:
Major Road Traffic Volume:
Minor Road Traffic Volume:
Average Major Road Volume :
Average Minor Road Volume :
Development Details
Date Range of Data Used: 2010 to 2012
State: FL
Country: USA
Type of Methodology Used: 7
Sample Size (sites): 341 sites
Sample Size (site-years): 1023 site-years
Sample Size (miles): 128 miles
Sample Size (mile-years): 384 mile-years
Other Details
Included in Highway Safety Manual? No
Date Added to Clearinghouse: Mar-08-2016
Comments: CMFs of converting urban undivided 4-lane arterials into 3 lane (1 lane in each direction with a TWLTL).